Author: aaronballman Date: Wed Dec 30 08:26:07 2015 New Revision: 256643 URL: http://llvm.org/viewvc/llvm-project?rev=256643&view=rev Log: When performing an implicit from float to bool, the floating point value must be *exactly* zero in order for the conversion to result in 0. This does not involve a conversion through an integer value, and so truncation of the value is not performed.
This patch address PR25876. Modified: cfe/trunk/lib/Sema/SemaChecking.cpp cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp Modified: cfe/trunk/lib/Sema/SemaChecking.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=256643&r1=256642&r2=256643&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaChecking.cpp (original) +++ cfe/trunk/lib/Sema/SemaChecking.cpp Wed Dec 30 08:26:07 2015 @@ -6983,7 +6983,7 @@ void DiagnoseFloatingLiteralImpCast(Sema SmallString<16> PrettyTargetValue; if (T->isSpecificBuiltinType(BuiltinType::Bool)) - PrettyTargetValue = IntegerValue == 0 ? "false" : "true"; + PrettyTargetValue = Value.isZero() ? "false" : "true"; else IntegerValue.toString(PrettyTargetValue); Modified: cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp?rev=256643&r1=256642&r2=256643&view=diff ============================================================================== --- cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp (original) +++ cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp Wed Dec 30 08:26:07 2015 @@ -38,3 +38,14 @@ void test0() { int y = (24*60*60) * 0.25; int pennies = 123.45 * 100; } + +// Similarly, test floating point conversion to bool. Only float values of zero +// are converted to false; everything else is converted to true. +void test1() { + bool b1 = 0.99f; // expected-warning {{implicit conversion from 'float' to 'bool' changes value from 0.99 to true}} + bool b2 = 0.99; // expected-warning {{implicit conversion from 'double' to 'bool' changes value from 0.99 to true}} + // These do not warn because they can be directly converted to integral + // values. + bool b3 = 0.0f; + bool b4 = 0.0; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits